[PATCH] s390: fix in-user atomic futex operation.
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
__futex_atomic_op needs to do an atomic operation in the user address space,
not the kernel address space. Add the missing sacf 256/sacf 0 to switch to
the secondary mode before doing the compare-and-swap. In addition add
another fixup for catch specification exceptions if the compare-and-swap
address is not aligned.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-s390/futex.h b/include/asm-s390/futex.h
index 40c25e1..1802775 100644
--- a/include/asm-s390/futex.h
+++ b/include/asm-s390/futex.h
@@ -11,23 +11,24 @@
#define __futex_atomic_fixup \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
- " .long 0b,2b,1b,2b\n" \
+ " .long 0b,4b,2b,4b,3b,4b\n" \
".previous"
#else /* __s390x__ */
#define __futex_atomic_fixup \
".section __ex_table,\"a\"\n" \
" .align 8\n" \
- " .quad 0b,2b,1b,2b\n" \
+ " .quad 0b,4b,2b,4b,3b,4b\n" \
".previous"
#endif /* __s390x__ */
#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \
- asm volatile(" l %1,0(%6)\n" \
- "0: " insn \
- " cs %1,%2,0(%6)\n" \
- "1: jl 0b\n" \
+ asm volatile(" sacf 256\n" \
+ "0: l %1,0(%6)\n" \
+ "1: " insn \
+ "2: cs %1,%2,0(%6)\n" \
+ "3: jl 1b\n" \
" lhi %0,0\n" \
- "2:\n" \
+ "4: sacf 0\n" \
__futex_atomic_fixup \
: "=d" (ret), "=&d" (oldval), "=&d" (newval), \
"=m" (*uaddr) \